The problem is that after formatting (3 times) and installing Windows XP SP2, few days later the computer stops working, some Windows files are missing, it all begins with normal usage or when the computer is idle, it ends with no other option then reboot. Then, Windows won't reboot, saying that a system file is missing (and the OS was recently installed). Is it a virus, the Windows copy or a hardware problem?

help me please, please pls pls

I use AVG and Avast anti virus , my driver is new version, windows i copy but a good copy it,s work on my second computer good,I use some programs but it is from official web side od the program (Cubase, goutar rig3,amplitube 2, toons ezdrummer, fxpansion) the last time (last formating) I wasn't instal program just XP and problem is exist ....
thanks ...

Hello,
I am not sure but did you try your hard disk in other system.connect it to antivirus installed computer and then scan it..i have face same problame but i connect it with other system and scan it i found a virus there after clean it.its working fine......

Don't run two antivirus programs at the same time , they will almost certainly fight each other for resources and file access. This can not only kill your machine's available resources, but potentially reduce their ability to actually detect problems.

Just run one in live scanning mode, and if you really want to then keep another around, not in active / scanning / protection mode and just run it manually from time to time (after temporarily turning the other one off).

Have you tried system restore? Access system restore via computer safe mode. If this does not work try getting Windows registry cleaner help. Sometimes upgrades cause registry issues, when these happen some computer functionalities usually suffer.

The registry cleaner should be able to help remove or fix the registry issues and restore your computer back to its normal state. Hope this helps